1. Field of the Invention
The present invention relates to a light modulator that modulates light to form an optical image and a projection-type display apparatus that uses the light modulator to display a projected image.
2. Description of the Related Art
In recent years, a liquid crystal projector is widely known as a projection-type display apparatus that displays a projected image. A liquid crystal projector is configured to modulate the light emitted from a light source by using a liquid crystal panel, which is a kind of light modulation panel, to form an optical image according to an image signal, enlarge and project the optical image through a projection lens, and display the enlarged image on a screen.
In the thus configured liquid crystal projector, in general, a housing thereof houses an air-cooling unit including an electric fan and an air passage duct. The air cooling unit produces an air flow along the panel surface of the liquid crystal panel, whereby the liquid crystal panel is cooled. The reason for the air cooling is that the heat resistance of the liquid crystal panel is lower than those of the light source, the power supply, and other components (see JP-A-08-262432 and JP-A-2001-318361, for example).